1. Field of the Invention
The present invention relates to a waterproof switch used in an door such as a tail gate, a backdoor, a trunk lid and the like of a motor vehicle.
2. Description of the Related Art
As a mechanism for opening and closing the tail gate, the backdoor or the like, for example, there has been conventionally a structure shown in FIG. 1 which corresponds to a structure described in Japanese Patent Application Laid-Open No. 2000-177397. FIG. 1 is a cross sectional view showing an opening and closing mechanism of a tail gate for opening and closing a rear opening of a motor vehicle.
As shown in FIG. 1, a tail gate 101 forms a closed sectional structure by combining an outer panel OP and an inner panel IP, and has a lock apparatus 103 in a lower portion thereof. The lock apparatus 103 is structured such that a latch is engaged with and disengaged from a striker 107 provided in a rear opening 105 of a vehicle body, whereby the lock apparatus 103 can lock the tail gate 101 and cancel the lock of the tail gate 101 with respect to a side of the vehicle body. An operation handle 109 is supported to the tail gate 101. The operation handle 109 and the lock apparatus 103 are interlocked by a connecting rod 111.
Accordingly, by operating the operation handle 109, it is possible to interlock the lock apparatus 103 via the connecting rod 111, cancel an engagement of the latch with respect to the striker 107 and cancel the lock of the tail gate 101.
However, as mentioned above, in the structure that the lock is canceled by the operation handle 109 formed by the link connection, a play is easily generated and an operating load of the operation handle 109 becomes great. Further, a weight is increased due to a weight of the operation handle 109 and the connection rod 111.
On the contrary, when the lock apparatus 103 is structured such as to be driven by a solenoid, a waterproof switch is provided in place of the operation handle 109 and the lock and the lock cancellation of the lock apparatus 103 are executed by the waterproof switch, it is possible to restrict the play, reduce the operation load and further reduce the weight as a whole, as is different from the link connection.
However, in the case of the structure in which the lock apparatus 103 is electrically operated by the waterproof switch, a waterproof property of the waterproof switch comes into problem.
That is, with respect to a penetration from an outer side of the outer panel OP, not only is it necessary to waterproof between the waterproof switch and the outer panel OP, but also it is necessary to achieve a waterproof function when the water penetrating between the outer panel OP and the inner panel IP from other portions is applied to the waterproof switch therewithin.
Accordingly, a seal member such as an O-ring or the like is required within and out of the outer panel OP, so that a number of the parts is increased, and it becomes troublesome to assemble and control the parts, whereby a cost is increased.
An object of the present invention is to provide a waterproof switch which can electrically open and close an opening and closing body of a vehicle body, for example, in the manner mentioned above, having a seal member for proofing water hold in a side of the waterproof switch, and can sufficiently proof water within and out of a panel without increasing a number of parts.
In accordance with a first aspect of the present invention, there is provided a waterproof switch comprising:
a base mounted to a panel constituting an door of a vehicle body and provided with a seal surface;
a push rod supported to the base and having a head portion facing from a hole of the panel, the head portion being pressed, thereby moving against an urging force so as to open or close a contact point;
a seal member provided with a head cover portion covering a head portion of the push rod, a panel seal portion opposing to the panel around the hole of the panel, and a base seal portion disposed in the panel seal portion with an interval and opposing to a seal surface of the base around the push rod; and
a case provided with a mounting and engaging portion mounted to the base in such a manner as to freely engage with and disengage from the base, and a seal assist portion interposed between a panel seal portion and a base seal portion in the seal member, pressing the base seal portion to a seal surface of the base in a mounting state of the mounting and engaging portion and closely attaching the panel seal portion to the panel at a time of supporting the panel seal portion so as to mount the base to a side of the panel.
In accordance with a second aspect of the present invention, there is provided a waterproof switch as recited in the first aspect, further comprising an engagement hole provided in one of the mounting and engaging portion of the case and the base and an engagement convex portion provided in the other, wherein the case is slid with respect to the base so as to engage the engagement hole with the engagement convex portion, and the seal assist portion presses the base seal portion to the seal surface of the base.
In accordance with a third aspect of the present invention, there is provided a waterproof switch as recited in the second aspect, wherein the seal assist portion of the case is constituted by a flange-shaped panel seal assist portion closely in contact with the panel seal portion, and an orbital-shaped base seal assist portion protruding from the panel seal assist portion and having a front end pressing the base seal portion.
In accordance with a fourth aspect of the present invention, there is provided a waterproof switch as recited in the third aspect, wherein the case has a drain hole communicating with an outer peripheral side of the base seal assist portion.
In accordance with a fifth aspect of the present invention, there is provided a waterproof switch as recited in any one of the first to fourth aspects, wherein the panel seal portion of the seal member has a crushed margin in an outer peripheral side of a surface opposing to the panel.
In accordance with the first aspect of the invention, the seal member is provided with the head cover portion covering the head portion of the push rod of the waterproof switch, the panel seal portion opposing to the panel around the hole of the panel to which the waterproof switch is mounted, and the base seal portion disposed in the panel seal portion with an interval and opposing to the seal surface of the base around the push rod, the seal assist portion of the case is interposed between the panel seal portion of the seal member and the base seal portion, the mounting and engaging portion of the case is mounted to the base in such a manner as to freely engage with and disengage from the base. The seal assist portion presses the base seal portion to the seal surface of the base in this mounting state, supports the panel seal portion and closely attaches the panel seal portion to the panel at a time of mounting the base to the side of the panel so as to establish a seal.
In the manner mentioned above, since the head portion of the push rod is covered by the head cover portion, the panel seal portion is closely in contact with the panel in the periphery of the hole of the panel so as to establish the seal. The base seal portion is pressed to the seal surface of the base so as to establish the seal. The water which is going to penetrate from an external portion of the hole of the panel facing to the head portion of the push rod can be waterproofed by the head cover portion and the panel seal portion. Further, with respect to the water penetrating to an inner portion of the panel from the other portions, it is possible to waterproof by the base seal portion. Accordingly, it is possible to sufficiently achieve a waterproof inside and outside the panel.
Further, since the head cover portion, the panel seal portion and the base seal portion can be integrally formed as the seal member, a number of the parts can be reduced, it becomes easy to control parts and assemble, and it is possible to reduce a cost.
Further, since the seal member can be held by attaching the case to the base before attaching the waterproof switch to the side of panel, an assembling operation can be executed in a significantly easy manner.
Further, when the lock apparatus provided in the door of the vehicle body is electrically locked or cancelled from the locked state by the waterproof switch, the play becomes significantly less than that of the link connection, it is possible to reduce an operating force and it is possible to reduce the weight.
In accordance with the second aspect of the invention, in addition to the effect of the first aspect, since the waterproof switch has the engagement hole provided in one of the mounting and engaging portion of the case and the base and the engagement convex portion provided in the other. The case is slid with respect to the base so as to engage the engagement hole with the engagement convex portion, and the seal assist portion presses the base seal portion to the seal surface of the base, it is possible to securely make the assembly of the seal member easy and it is possible to securely waterproof in the side of the inner portion of the panel.
In accordance with the third aspect of the invention, in addition to the effect of the second aspect, since the seal assist portion of the case is constituted by the flange-shaped panel seal assist portion closely in contact with the panel seal portion, and the orbital-shaped base seal assist portion protruding from the panel seal assist portion and having the front end pressing the base seal portion, it is possible to securely press the base seal portion by the seal surface of the base by means of the orbital-shaped base seal assist portion when attaching the case to the base. Further, when attaching the base to the side of the panel, it is possible to securely bring the panel seal portion into close contact with the side of the panel by an assistance of the panel seal assist portion. Accordingly, it is possible to more securely achieve a waterproof function.
In accordance with the fourth aspect of the invention, in addition to the effect of the third aspect, since the case has the drain hole communicating with the outer peripheral side of the base seal assist portion, the water penetrating to the outer peripheral side of the base seal assist portion is discharged to the external portion from the drain hole, and it is possible to restrict a secondary problem caused by the water stored in the portion mentioned above.
In accordance with the invention as recited in the fifth aspect, in addition to the effect of the invention as recited in any one of the first to fourth aspects, since the panel seal portion of the seal member has the crushed margin in the outer peripheral side of the surface opposing to the panel, the crushed margin is crushed at a time of closely bringing the panel seal portion into contact with the panel, whereby it is possible to achieve a secure waterproof.